Brushing devices of this kind are used, in particular, on machine tools in order to grind, polish or clean the surfaces of workpieces and to deburr or round off the edges of workpieces. The fibre rods, which can consist, for instance, of a ceramic material, are subjected to wear and tear during the said working operations. The extent by which the free ends of the fibre rods protrude beyond the protective sleeve must therefore be periodically readjusted. In known brushing devices, a holder carrying the fibre rods has a locking screw, which juts through a longitudinal slot in the protective sleeve. For the readjustment of the said extent, the locking screw is loosened, the protective sleeve axially displaced by an amount, and the locking screws then tightened again. This requires for each readjustment operation manual interventions, which are associated with a stoppage of the machine.
Document WO2015/178273A1 describes a brushing device with mechanical readjustment of the relative position of the protective sleeve and of the fibre rods. This is enabled by a nut-spindle combination, which is connected to the fibre rods and the protective sleeve. For the readjustment, the nut and the spindle must be rotated relative to one another, which is achieved by a relatively complex design of the brushing device, which design, moreover, makes the use of a standard tool holding fixture for the brushing device practically impossible.